Need Tips for trading player/transfer list

Excuse me first if my thread is violating the regulation in this forum or so.

First of all i'm new at this game, and i'm try to build my squad. I'm selling the player that has low stat and buying the player with higher stat in transfer list, but i always ending up having a small squad, i can't sell my player anymore though the line up is still weak. Can anybody give me tips about that?

@graceyudha , here is my tips. try selling your best players first until the match start. Buy a new player after each sold. That way, you will always have players to sell. When the match started, sell your best reserve player, and always replace with the better one. At least try to maintain that you have the reserve player. Do this cycle until you satisfied. After 15 days, you should be able to increase you squad value from 30M to 200M or more.